Five months after the events of the last series, DS Marcella Backland is called to a house where a workman has drilled through a wall and discovered an ear. When the wall is taken down, Marcella is horrified to discover that the ear belonged to Leo Priestley, a 7-year old boy who's been missing for four years and who knew her son. Leo was meant to walk home with Edward, Marcella's son on the day he went missing.
Leo's discovery puts Marcella in confrontation with a previously convicted child abuser, Phil Dawkins. Dawkins is open to Marcella about being a non-practising paedophile – his urges are deemed unacceptable by society and he takes precautions to control them. Following his release from prison he's tried to move on to an acceptable life but Marcella struggles to move past Phil's admission.
